Every winter, pods of Pacific humpback whales make the 3,000-mile swim from the chilly waters of Alaska to bask in Hawaii's summery shallows, fluking, spy hopping, spouting, breaching, and having an all-around swell time. About 1,500 to 3,000 humpback whales appear in Hawaiian waters each year.

Humpbacks are one of the world's oldest, most impressive inhabitants. Adults grow to be about 45 feet long and weigh a hefty 40 tons. Humpbacks are officially an endangered species; in 1992, the waters around Maui, Molokai, and Lanai were designated a Humpback Whale National Marine Sanctuary. Despite the world's newfound ecological awareness, humpbacks and their habitats and food resources are still under threat from whalers and pollution.

The season's first whale is usually spotted in November, but the best time to see humpback whales in Hawaii is between January and April, from any island. Just look out to sea. Each island also offers a variety of whale-watching cruises, which will bring you up close and personal with the mammoth mammals; see the individual island chapters for details.

In the excitement of seeing a whale or a school of dolphins, don't forget that they're protected under the Marine Mammals Protection Act. You must stay at least 100 yards (the length of a football field) away from all whales, dolphins, and other marine mammals. This applies to swimmers, kayakers, and windsurfers. And yes, visitors have been prosecuted for swimming with dolphins! If you have any questions, call the National Marine Fisheries Service (tel. 808/541-2727) or the Hawaiian Islands Humpback Whale National Marine Sanctuary (tel. 800/831-4888).

Money-saving tip: Book a snorkeling cruise during the winter whale-watching months. The captain of the boat will often take you through the best local whale-watching areas on the way, and you'll get two activities for the price of one. It's well worth the money.